Calorimeter



C. V. BOYS CALORIMETER Nov' Filed Dec. 27 1921 3 Sheets-Sheet 1 Nov. 25, 1924. 1,5%,703

' C. V. B OYS CALORIMETER Filed Dec. 2'7, 1921 Nov. 25, 1924. www3 C. V. BOYS CALORIMETER Filed Dec. 2'7 192] 3 Sheets-Sheet 3 Patented Nov. 25, 1924.

CHARLESVERNON BOYS, OF LONDON, ENG-LAND.

cnroariunmna.

Application rled December 27, 1921.. SerialNo, 525,220.

To @ZZ whom t may concern:

Be it known that I, CHARLES VERNON BoYs, F. R. S., a subject of the VKing of Great Britain and Ireland, and residing at 66 Victoria Street, Westminster, London, S. W. l, England, have invented certain new and useful Improvements in Calorimeters, of which the following is a specification.

My invention relates to calorimeters, and although having special reference to the in= strument described in my prior applicationl ing the two thermometer bulbs of unequall capacity to compensate for the varying temperature of the inlet water as in my former application is avoided.

Referring to the accompanying diagrammatic drawings:

Figure l is a vertical section on line l-l of Figure 2 through the calorimeter casing and through the hot side of the calorimeter showing the cold side in elevation;

Figure 2 is a plan of the parts shown in Figure l with certain parts in section;

Figure 5 is a side elevation of the adjustable bell crank lever, of which Figure 3a is a detail;

Figure 4 is a vertical section showing a modified construction suitable for non-recording use, but with the upper part of the heat interchanger in elevation;

Figure 4al is a sectional plan on the line 41--4a of Figure 4.

Figure 5 is a sectional elevation of the air saturator taken on the line 5 5, Figure l.

Parts or closely corresponding parts of my prior application mentioned above which appear are lettered with their original letters for ease of comparison, and the letters of like parts are the same in all the figures.

It will be apparent from the figures that the water delivered to the calorimeter at a known rate enters the pipe C1 and so passes to the cold thermometer Water vessel C4, thence by the tube C7 to the water ring C, up through the interchanger B, as shown on the right side in Figure 1 and Figure 4 and through the neck B1 of the hot thermometer vessel C5 andl out by the tube C27 to the air saturating box A3 from which it escapes by the pipe AM- (Figure 5) either to a drain, or as I prefer through a radiator or pipe of extended surface where it acquires the temperature of the room to a tank to be pumped and used again. The gas measured and delivered at a known rate enters the burner tube C21 and issuing therefrom burns producing the Haine. The air for combustion can only reach the combustion chamber C15 by passing along the flat passage 020 below the base C14 of the calorimeter having'come from the space around the cold thermometer vessel C, through the large hole B2. The cold and hot thermometer spaces are separated by the partition B3. The way in which the air enters the cold thermometer space is the subject of one of the reiinements of this specification and is described in connexion therewith.

The products of combustion descend through the passages lL in the interchanger, as shown on its left side in Figure l, and with any liquid condensed pass to the exit gas passage B5 by way of the annular trough B6.

The heat interchanger is made of sheet metal preferably of lead autogenously soldered lfor continuously recording calorimeters, but other met-als such as copper or brass sott soldered might be used for instruments not in continuous use. Lead autogenously soldered is well known to resist the destructive action of the sulphurous vapours of burning' gas and so is prereix` able more especially for continuous use.

It will be evident that other material than metal. which can be made into sheets and joined and which is sufficiently heat conducting and incorrodible niigl'it be used for the interchanger.

As will be seen from Figures l and 2, the heat interchanger is made of sheet metal bent or folded so as to contain numerous narrow up passages BT for the circulating water and voluminous down passages B4 for the gases of combustion.

ln the horizontal section Figure 2, taken o-n the line -t Figure l, the metal o-f the heat interchanger B is shown as part of a single strip of thin sheet metal bent bacio wards and forwards radially so as Vto enclose the narrow waterways B7 between its own folds and between these and the casing C5. At the upper and lower ends of said heat interchanger the radial waterways are somewhat widened as indicated in the figures so that there may be a sumcient Water circulation up the inner folds of the metal. These inner folds are arranged to be in contact or nearly so, in order thatthe ascending and descending gases may not intermix, and any accidental chinks` left between these will in use be stopped by condensed water. Below the slight widen ings of the radial .vaterways at the lower end the folds are pinched together Bb. and soldered together and the outermost parts are bent inwards sufliciently for the interchanger to be driven into the ring Cf, and soldered thereto so that water of circulation cannot escape below.

At the upper end of the interchanger the outermost parts are bent inwards B1, and the radial webs are cut ofi' at an angle as shown in Figure l, and therepinched together and soldered B10, so that rising` water can escape upwards and outwards in the numerous narrow passages B7 between the bent-in portions. Three or more of these radial portions are carried higher than the rest and being each made with a notch carry a flat domev of fused silica S or equivalent material which in use becomes hot enough to vprevent water from condensing upon it, and as it is incorrodible, pimples of corroded metal immediately above the flame cannot be formed. lil/There these hot gases .impinge directly upon water cooled metal, condensation of water occurs and if the metal corrodes and forms a pimple the condensed water drops upon the burner and puts out the flame.

Immediately above the silica dome a metal dome B12 is also provided and this is soldered all round as shown at B1P to the bent-in portions aforesaid, and thus the hot gases are able to move outwards and downwards and the water is able to more upwards, but is not able to enter into the passages for the gases. By this construction I am able to obtain a heat interchanger of great, simplicity and cheapness of censtruction with a very large surface for the cooling of the gases so that `it may be made compact and it is durable if made of lead. A further advantage is the very small water content and the large cross-section of the down gas-ways. As will be seen at B11, Figure 2, the ends of the strip of sheet metal are bent inwards into one of the down-gas passages and there soldered together. l have shown one form of bent sheet metal interchanger, but it is evident that such an interchange-r having the. special features and advantages described may be made in many forms and in two or more parts, but l claim all such constructions as equivalents. p

The water after receiving its heat from the interchanger passes through the small hole B15 in a neck B1 of the hot water vessel C5 where any differences of temperature of various streaks of water are eliminated by mixing. F rom the neck the water passes through a number of holes B1G into the upper section Where it passesin a thin sheet round the hot thermometer T5 of improved construction. The cold water entering the cold thermometer vessel G1 is shown entering directly from the inlet pipe C1, and if as already mentioned this water has already been brought tothe temperatune. of the room this is permissible. If, however, the cold water entering the calorimeter is not brought to the temperature of the room the pipe C1 should be carried round the cold water compartment before entering the cold thermometer vessel C1, so that the. air for combustion shall be brought to the temperature of the water as described in my said former application.

The operative thermometers according to my present invention are of simplified construction and the hot and cold thermometers yare identical in capacity and form, and they are made without connecting pipes and separate aneroid diaphragm bores. As seen in vertical section in Figure l, the hot water thermometer T5 consists of a piecev of tube TT of nearly the same diameter as the upper section of the hot water vessel C5 and the upper and lower ends are closed by corrugated aneroid discs B17 and B1s respectively, and the cold thermometer hidden within the cold thermon'ieter vessel C1 is identical.

To each ofthe lower corrugated covers B1., is soldered a. conical support Bm designed to rest in a conical central recess B2O to locate it accurately, while the upper ends have soldered to them spigot Viilling blocks B21 in which the screws T1S force the balls B22 into conical recesses Bwto seal in the liquid. For the reasons givenin my former application,V I prefer to employ amyl-alcohol for filling these thermometers. Operative thermom- 'eters of this simple construction are very easilyfiilled by meanssimply of a capillary funnel, and then when apparentlyV rulli a slight spinning of the. conical` point will bring any air bubbles to the centre where they ,can be ejected, liquid taking-their place. rlhey have the further advantage that they are wholly immersed in the waterand the whole of the liquid in either thermometer is at the same temperature. The temperatures are indicated. by the distances between defined axial points at the two ends or each thermometer. As the whole expansion is very small a most. precise and powerful magnification system is essential and' this can readily be made as shown in the drawings. Each thermometer carries a cap Bm screwed over the spigot block, and these caps carry axial points B25 B20, preferably screw adjusted as shown, one acting upwardly on its lever B27 and the other downwardly on its lever As shown the hot bulb is the one with the downward action, but it is possible to arrange that the coldone has the downward action. Each axial point acts on the short end of its particular lever, and as will be seen from the drawing the levers have each the same magnification; in the example shown 2% to l. The levers are carried on pillars B2., attached to the lid B30 of the hot; water compartment which lid is detinitely` located. In the example shown the Jrul crurn axes are equidistant from the axis or the hot water compartment, but this while symmetrical and convenient is not essen-tial. Both levers rest in notches at the upper ends of their respective pillars and the cold thermometer lever which is pushed upat each end as will be made clear, is held down on to its ulcrum B31 by the spring B32. This construction is much more convenient than the use of overhead notches up against which the :forces at the two ends would keep the lever engaged. The outer ends ot the two levers terminate in the same transverse plane and the hot thermometer lever B2S carries a bell crank lever D working in a transverse vertical plane by a notch D1 at one end of its short arm while the cold thermometer lever B27 presses down on the other end D2 ot its short arm and so overcomes a small backward pull applied to` the end D3 of the long arm vertically below. The short arm ot this lever is made adjustable as to length by the screw D1., as in made clear in Figure 3.

It will be seen that with such a construction the backward or forward movement of the lower end D3 of the bell crank lever is determined only by the diiterence of temperature of the two operative thermometers for any change of temperature common to the two merely raises or depresses the bell. crank lever as a whole by a very small amount. The small' backward force co-nstantly applied to the lower end of the bell crank lever is transmitted through the link D5 from an arm D6 outstanding from the axis ot' theintegrater lantern which itself in the' example shown is constantly urged by a spring (not shown) to turn in a rlockwise direction as see-n from above.

This Construction without pivots except those of the integrater trame is one easy to make, free from friction and backlash and kinema-tically complete. All the elements rest by knife edges or points in notches or conical holes, and each one can be lifted ott at any time. The lever system derives its motion from the variation ot level ci3 the determining` points carried by the two thermometers and these twc thermometers each rest by a cone in a conical depression in a rigid metallic structure.

As seen in Figure. :2, tubes B33 BH are soldered to the cold and hotl thermometer vessels respectively so as to contain standard mercurial thermometers by means of which the action of the operative thermometers may be checked. These two tubes are carried up through the lid of the calorimeter casing C C to a convenient level at which to read the mercury index ot each. The upper ends ot these tubes are slit longitudinally and sprung inwards so as to hold thel thermometers at the desired level. By this means the mercurial thermometers are surrounded by metal at nearly the same temperature as lthe bulbs, and the errors due to exposed stem are almost entirely eliminated. The tube Bim belonging to the hot vessel cannot be seen in tho vertical section Figure l, as it is in trent cil' the plane ot section, but B33 belonging to the cold vessel is seen partly broken away., as this part is shown in elevation.

As will be seen in Figure 2, the conducting shield G25 is brought round outside the thermometer tube B34. The shield C27, is kept in place by the split ring of willow or other non-conducting material B37, which is secured as shown by string or wire. The neck of the hot water vessel which locates it and is strengthened by it7 serves to prevent local heat currents from being set up which act as local regenerators.

Referring again tothe thermometer lever system, it will be seen that either of the screws T28 or ll28a may be used to bring the pen carried by the lantern, as de cribed in my said former application, to the place on the record sheet corresponding to the temperature of difference shown by the mercurial thermometers, but the screw T28 entering the lid and covered by a special cover B36 is the more convenient. It will be evident also that the scale ot mag-hincation is adjustable by means of the screw DAL which alters the length of the short arm of the bell crank lever D. Further provision is made for larger variations of scale to meet special requirements as a number ot conical holes are provided in the arm DG which is the short arm ot the pen leve-r and the link D, can be made to engage any one et these. lt will be evident also that i'j for any reasons ten'iperatures higher or lon/'er than those intended are developed, no strain is thrown upon the lever system when the pen is prevented trom 'further movement by reason of the engagement ot the lantern lf, with the sides et the integrating drum L, tor the hot thuernionicter or the cold thermometer lever Will be lifted oil" its seat and will settle down again when normal temperatures are resumed.

lt will be seen trom Figure l, that the integrati wheel l, is carried on a pivoted trame vl, carried on the mintilevcrs il, attached to the lantern l, and in part coui'n ter-balanced by the Weight .ly By this means the pressure between the integrating Wheel and drinn may readily be made definite and small and the weight ci" the integrating trame is taken by the pivot l, resting on the screw ilu.. This construction gives rise to a minin'ium oit' friction and interferes in no observable degree with the accuracy ot the record.

When the improved construction of interchanger is used in a nen-recording calorimeter the operative thermometers are not required and mercui'ial thermometers are placed directly in the entering` and leaving water, and only narrow Water tubes are then required instead of the large vessels required by the operative thermometers.

ln order to avoid the considerable liuctuations ot temperature Which would result it' the Water passed direct `from the surface of the interchanger to the hot thermometer, l make use ot the equalizer which l have used in my original gas calorimeter as shown in Figure el. ln this, the upper part et the interchanger is seen in elevation and above it the equalizer in section. This consists ot tivo discs El E, oi sheet metal separated from one another and trom the interchanger below and the top et the hot Water chamber above by open spirals of sheet metal E, so that the Water in passing through as shoivn by the arrows, takes spiral routes and interchanges small difference ot temperature between successive portions o'i' Water by conduction through the metal and in part by leakage it the spirals do not lit accurately. Vhen so used as a non-recording calorimeter there is no necessity to use the Water or gas measuring and delivering` system as described in said former application, and, of course, the integrating system and pen recording drum are not required. While this is true the general system as described including the Water and gas measuring and delivering devices (but Without the means for correcting gas volumes), the

equal to that of the gas and air together before combustion, but is less, the exact amount et' contraction depending on the composition oit the gas. This contraction may give rise to error more or less and positive or negative according to the hygrometric state of the air. lt by Way of example, v

the volume of air is seven times that of the gas betere combustion and the contraction is one eighth of the Whole so that the volume ot the gas disappears, then it the air before combustion is sin sevenths saturated With Water vapour and the gas after leaving the Wet meter is saturated, the products being necessarily saturated, the amount of Water leaving as vapour Will be equal to that entering as vapour, and only in such case the error referred to does not arise. It, hovvever, as in dry-Weather, the air is less than six sevenths saturated, then more Water leaves the calorimeter as vapour than enters it as vapour, and the heat necessary to convert this amount of Water into vapour at the temperature ot the eiiluent gases is abstracted from the calorimeter and to this eitent the record is too low. Conversely, it the air is more than six sevenths saturated vapour is condensed in consequence of the contraction and generates heat which Was not caused by the combustion ot the gas, thus making the record too high.. Further the higher the temperature at Which the cold Water enters the calorimeter the greater Will be the error positive or negative due tov this cause.

Se tar as I am aware no attempt has been made to correct for this error, but saturation of the incoming air has been employed ensuring too high a resultat all times. The Whole error due to contraction is never great, but it is persistent. lln moist climates like that of England this error is seldom serious, but in dry countries, such for instance, as the east side of America, thev negative error may amount to a considerable traction of one per cent. I provide means tor avoiding this error, or at least reducing it to a great extent, which l have illustrated in Figures l, 2 and 5.

The Whole ot the air for combustion is led to the combustion space of the calorimeter through the Wide flat passage C20 underl the calorimeter, the air entering said passage through the hole B2 at the `bottom of the cold Water compartment. rihe air can only reach this hole by con'iing down the passage A seen in plan in Figure 2, the partition which terms this passage extending up to Within oneor two inches et the lid. Air can only enter the cold Water chamber either from the room directly through the narrow passages A2 or indirectly through a saturating device A:p and thereafter through the orifice A4.

In order to determine the suitable proportions ot the air entering directly and indirectly I attach two light valves A, and AG to a lever AT, and I cause the lever to move in consequence of the change ot dimensions Or Weight ot a hygro-metric substance in such manner that if the ai!l in the cold Water compartment is drier than a predetermined quantity the lever shall move so as to obstruct the entry of the air from the room through the passages A2 and to give more iree access to the air coming` from the satu rater A., by the orifice A4; conversely, it the air is meister than the predetermined amount, the movement is in the opposite direction. It the air of the room is already as moist as this or more so, then beyond closing the orifice AAJ by which the saturated air enters nothing more can be done. In the Figures l and 2 I have shown as a hygrometric Vsubstance a hair AS carried up the Whole height or nearly so of the cold Water compartment, round a pulley A., and down again to the lever A7. The hair is secured at the other end to a Winch A10 With milled head A11 outside the calorimeter case C C so that the position ot the valves may be ad-l justed. A Window A12 is placed opposite the valves se. that their position may be seen.

The operation of the saturator is as tollows :-Air can only enter at the end Am along the L-shaped box, the plan of which is shown dotted. in Figure 2, and the cross section ot' Which on the line 5-5 of Figure 1 is shown in Figure 5. Into this end of the box the Warm Water from the calorimeter enters by the pipe C27 and travelling along the box leaves by the pipe A14. lThe cold Water from the Water Wheel I-I3 passes by the pipe Al5 into the other end of the saturator box and it leaves by the same pipe A14 by which the Warm Water leaves. This cold Water also passes over the leg A17 of the L-shaped box by which the air reaches the orifice A4. A Water tumbling device such as A16 may be included in the length ot the box so as to rotate and increase the surface of Warm and cold Water in contact with the moving air. By this means theair first passes over the Warm Water Where it readily absorbs moisture, then over cold Waterv Where it is cooled to the temperature of the Water,

and superiiuous vapour, if any', is condensedV and is then tree to enter the cold 'Water compartment cooled and saturated to the extent determined by the position oi' the valves. By this means the air entering the combustion chamber may be kept at any desired degree of saturation which is not less than that of the air oi the room.

Any source ot heat other than the flame, whether continuous or intermittent, may be measured by means of the recording and integrating calorimeter. Electrically produced heat might be measured or such heat capable ot very accurate measurement; may be used in the place ot the mercurial thermometers for Calibrating or adjusting the recording system. rlhe recording and integrating calorimeter may in particular be employed With very great advantage tor measuring the heat developed in a calorimetric bomb. For this purpose the interchanger and 'flame are replaced by the bomb which is carried on a plate which like the ring C, can be screwed to the base ot the calorimeter. Then the water and clock are started and the instrument is lett until the record made by the pen shows that steady conditions have been attained. Then the contents of the bomb are ignited as usual electrically and the instrument is lett to itself. After sufficient time for the steady conditions again to be attained the record can be seen and measured. The area enclosed by the heat curve and straight line joining the beginningand end of the disturbance is a measure oi the heat developed in the bomb, and this may be read direct on the integrating Wheel. For this purpose the integrating drum would advantageously be geared so to turn more quickly.. and the scale of magnification ot the pen movements and the iiow ot water would be chosen to be suitable tor the conditions ot the ere periment.

Having now described my invention, what I claim as new and desire to secure by liet ters Patent is:-

i. A recording calorimeter including in combination an operative thermometer formed of a rigid cylindrical vessel provided at each end With a resilient disc, a fixed abut ment supporting the centre of one disc and adjustable operative means abutting the centre ot the other said disc.

2. The combination in a recording calorimeter of tivo identical hot and cold opera tive thermometers, a separate lever operatively connected to each and a third lever co-acting with said first-mentioned levers to operate in the third dimension of space.

3. The combination in a recording calorimeter of tvvo identical hot and cold operative thermometers, a separate lever operatively connected to each and a third lever co-actingwith said tirst-fmenticued levers to operate inthe third dimension of space,

,said third lever incorporating leverage adpartly balanced supporting traine for the injustment means. tegrator dise rigid with said lantern frame 4. The combination inarecording caloriin- Work. 10 eter incorporating a drum and disc nite- In testimony whereof l have signed my 5 grating device of a pivotal lantern frame naine to this specilioaton.

Work, supporting means for said framework independent of the integrator drum and a A CHARLES VERNON BGYS. 

